The present invention relates to a process for preparing a resin having a low iodine value, and more particularly to a process for preparing a resin having a low iodine value, in which residual unsaturated bonds, which cause the coloring or deterioration of weatherability of the resin, are decreased, and which can be suitably used as, for instance, raw materials for flame retarders, adhesives and the like.
Conventionally, flame retarders have been prepared by reacting various resins (polymers) with a halogen-containing compound such as a bromine-containing compound. However, these resins (polymers) usually have residual unsaturated bonds in its molecule. Therefore, when the resins are reacted with the halogen-containing compound, there is a defect that an obtained resin is colored or weatherability of the resin deteriorates. Accordingly, after the residual unsaturated bonds in the resin are saturated, that is, an iodine value of the resin is lowered, the resin is reacted with the halogen-containing compound to use as a flame retarder.
As a method for lowering the iodine value of the above-mentioned resin, for instance, a process comprising adding hydrogen to the residual unsaturated bonds in the resin, and the like are cited. However, this process usually necessitates a complicated process under pressure and there occurs a problem that a huge investment in plants and equipments and running cost are required.
An object of the present invention is to provide a resin which is not colored and has excellent weatherability.
Another object of the present invention is to provide a resin which can be preferably used as a raw material for flame retarders, adhesives and the like.
A further object of the present invention is to provide a process which can easily and economically decrease the iodine value of a resin without a complicated process.
These and other objects of the present invention will become apparent from the description hereinafter.